Cast from How the Universe Works
Mike Rowe
Narrator
Erik Dellums
Himself - Narrator
Lawrence Krauss
Himself
Michio Kaku
Himself
Michelle Thaller
Herself
Phil Plait
Himself
Albert Einstein
Himself (Archive footage)
Richard Lintern
Himself - Narrator
Narrator
Himself - Narrator
Himself
Himself
Herself
Himself
Himself (Archive footage)
Himself - Narrator